Nozzle



T. A. HENSHAW ET AL Dec. 4, 1956 NOZZLE 2 Sheets-Sheet 1 Filed Oct. 27,1953 1 n [1211 tors WON/75 Ar/vma/vy i/EAAS/IIM .5204 A E/wv-asav,Attorney Dec. 4, 1956 T. A. HENSHAW El'AL NOZZLE 2 Sheets-Sheet 2 Filed001:. 2'7. 1955 A Home y United States Patent Company Limited,Brentford, England, a British com- Pa y Application October 27, 1953,Serial No 388,476

Claims priority, application Great Britain November 3, 1952 3 Claims.(Cl. 299-117) This invention relates to nozzles adjustable to vary theextent to which liquid delivered through the nozzle 7' spreads out fromthe axis. The invention is particularly applicable but not limited tonozzles for delivering foam for fire-extinguishing purposes.

It is an object of this invention to provide an improved nozzle by whichthe liquid delivered by the nozzle can either be caused to emerge as arod-like jet or can be given a rotary movement which causes scatter dueto centrifugal force.

Another object of the invention is so to provide vanes inside a nozzlethat by varying the angle between the vanes and the axis of the nozzlevarying degrees of spread can be obtained.

According to the invention vanes extending substantially longitudinallyare mounted in a nozzle formed by an open-ended and preferablycylindrical tube between positions in which they are parallel to theaxis, so that a rod-like jet is produced, to positions in which they lieat varying angles to the axis, so that the liquid in passing through theinclined channels formed between the vanes 2,772,923 Patented Dec. 4,1956 ICC is given a rotary movement which causes scatter due tocentrifugal force.

The preferred constructions are shown in the accompanying drawings, inwhich:

Figure 1 is a longitudinal section through one nozzle;

Figure 2 is a section on the line IIII in Figure 1;

Figure 3 is a section similar to Figure 1 through a second nozzle;

Figure 4 is an edge view of a modified vane; and

Figures 5 and 6 are respectively a section through and a plan of anothermodified vane.

Referring first to Figures 1 and 2, the nozzle shown is intended for useon the end of a foam generator to which it is joined by a connector 2.The nozzle consists of an open-ended'cylindrical tube 3 in which fourvanes 4 are mounted. Each vane is a flat metal plate extendinglongitudinally within the tube 3, and is fixed midway between its endsin a spilt pin 5 which projects radially into the tube 3 from a socket 6screwed into an opening in the wall of the tube. The socket 6 forms abearing for the pin and is covered by a cap 7. Each vane 4 can thereforeturn with its pin 5 about the axis thereof.

The width of the vanes is less than that of the radius of the tube, andthey leave a central axial zone of small radius unobstructed. Both thecircumferential edges of each vane 4 are curved, the outer edge of eachvane being curved to conform to the inner wall of the tube 3 in theposition of maximum inclination to the axis. The vanes are mounted sothat these outeredges nearly touch the inner wall of the tube in thisposition as shown in chain lines in Figure 2. I

The vanes 4 are all mechanically connected to'a ring 8 encircling thetube 3 and mounted to turn on it without moving axially, the ring beingguided by the engagement of screws 9, which project radially outwardsfrom the tube 3 man annular slot 10 in the ring. O-rings use; Themechanical connections between the nng 8.

and the'vanes tconsist ofia lug 12 on each vaneprojecting through a slot13 in the wall of" the tube 3 and entering a slot 14 in the'end of ascrew 15. Each screw 15 screws into an internally threaded boss 16integral with the ring 8 and projects into an annular recess 17 in theinner surface of the ring. The screws 15 turn with the ring, and whenthe ring is turned one or other wall bounding the slot 14 of each screwengages the lug 12 in that recess and so causes the vane 4 to turn aboutthe axis of the pin 5. With the construction shown there is adequatefreedom of axial movement between the lug and the ring to allow theturning movement to take place, the lugs sliding freely through theslots 13 and 14 and the recess 17. The length of the slots 13 determinesthe extent of the angular movement of each vane, which may be, forinstance, 45.

In operation the nozzle will produce a rod-like jet if the vanes are allparallel to the axis. By turning the vanes slightly the effective zoneof the jet, that is to say, the area it covers at a distance from thenozzle may be adjusted without much interference with the flow andtherefore without necessarily reducing the effective range. However, byincreasing the angle further the elfective range may be shortened. Thus,if in tackling a fire the operator finds he is too near to allow foam tofall quietly on to the fire he may spread the foam to a wider angle andin so doing shorten the efiective range and thus form a uniform blanketof foam over the fire without having to change his position. Forinstance, with one nozzle made as shown in Figures 1 and 2 it is foundthat at a range of feet an effective zone of influence of 4 feetdiameter may be increased to 12 feet by turning the vanes through asmall angle, whereas at a range of 20 feet the foam can be effectivelyspread over a zone of 20 feet diameter by turning the vanes to theirmaximum inclination to the axis without altering the supply pressure.

In the nozzle shown in Figure 3, the vanes are arranged to lie somedistance from the wall of the tube 3 so as to leave an annular passage18 between the vanes and the wall. Some of the foam flows uninterruptedthrough this passage and impinges on the diverging spray and thusproduces increased scattering.

Instead of being flat plates, the vanes may be streamlined axially, asshown in Figure 4. If desired, they may be drilled or provided withsmall obstructions 19, as shown in Figures 5 and 6, to cause breaking upof the spray.

The number of vanes may vary with the diameter of the nozzle, the degreeof spreading required and the velocity of the foam or other liquid to bepassed through the nozzle. Two or three vanes, as well as the four vanesshown, are found to give satisfactory results.

A nozzle according to the invention may be constructed as an adaptor forconnection to a normal foam outlet nozzle on hose if the foam isgenerated at a remote position, or may (as shown) be embodied in a foamgenerator of the kind commonly known as a foam branchpipe.

We claim:

1. A nozzle comprising a tube open at both ends, a plurality of vanesextending longitudinally within said tube, means located at the centerof said vanespivotally mounting said vanes to said tube, said meanslying in a common plane perpendicular to the axis of said tube, andsupplying substantially radial axes for turning movement of said vanes,and means for turning said vanes by actuating one end of said vanes,said second means comprising a ring encircling said tube and mounted toturn on it i 4 v y 3. A nozzle according to claim 2 in which the slotsin the tube are arcuate.

References Cited in the file of this patent UNITED STATES PATENTS992,314 Wheatley May 16, 1911 2,083,186 Anderson June 8, 1937 2,435,091

Meyer 1 Jan. 27, 1948

